Call not completed or has ended. Audio Call from communicator to communicator.Error ID 52001


  • Some of users in my lab environment having problem when they call each other. There Mic Headphone are fine.  i have deployed Lync in a lab at domain. my users are also from domain and some on workgroup. Workgroup users are calling each other. But Audio Calls between domain users is causing that error. Desktop Sharing , Whiteboard , Polls etc all are working well.


    Friday, January 14, 2011 6:36 AM

All replies

  • I would suggest you

    - enable logging on the lync server and review the logs
    - enable logging in Lync client on both sides, retry, and use the Logging Tool to view the client logs. They are saved in c:\users\<user>\tracing

    It might provide more information on the reason why the call is not completed.

    Technical Specialist Microsoft OCS/Lync & UC Voice Specialisation -
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    Friday, January 14, 2011 9:34 AM
  • Dear Ruben,

    Issues is only the Computers which are domain-joined to domain (Note: i didnt have any domain admin rights here, its my company's live domain ) , 

    My Lab domain is The users from domain are able to make desktop shairng, IM chat, Whiteboard etc except the Lync Call. we all are in the same network. The error i mentioned at the top is shown when i call to users which are coming frm domain-joined computers.

    Note: There is no Enterprise Voice and Edge Services installed at domain.

    What is clicking in my mind is that , is it a restriction of SRTP/RTP ports at

    So i have totally disabled firewall of one user frm domain still the same problem.

    Where i have to allow that traffic to be routed at

    Any idea, why is that happening? 

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    Friday, January 14, 2011 1:40 PM